package xpn.platform.modules.login;

import java.security.Key;
import java.security.Security;

import javax.crypto.Cipher;


public class SyncDES {
    private static String strDefaultKey = "Sync!FourA135";
    private Cipher encryptCipher = null;
    private Cipher decryptCipher = null;

    /**
     * 将byte数组转换为表示16进制值的字符串，
     * 如：byte[]{8,18}转换为：0813，
     * 和public static byte[] hexStr2ByteArr(String strIn)
     * 互为可逆的转换过程
     * @param arrB 需要转换的byte数组
     * @return 转换后的字符串
     * @throws Exception 本方法不处理任何异常，所有异常全部抛出
     */
    public String byteArr2HexStr(byte[] arrB)
        throws Exception
    {
        int iLen = arrB.length;
        //每个byte用两个字符才能表示，所以字符串的长度是数组长度的两倍
        StringBuffer sb = new StringBuffer(iLen * 2);
        for (int i = 0; i < iLen; i++)
        {
            int intTmp = arrB[i];
            //把负数转换为正数
            while (intTmp < 0){
                intTmp = intTmp + 256;
            }
            //小于0F的数需要在前面补0
            if (intTmp < 16){
                sb.append("0");
            }
            sb.append(Integer.toString(intTmp, 16));
        }
        return sb.toString();
    }


    /**
     * 将表示16进制值的字符串转换为byte数组，
     * 和public static String byteArr2HexStr(byte[] arrB)
     * 互为可逆的转换过程
     * @param strIn 需要转换的字符串
     * @return 转换后的byte数组
     * @throws Exception 本方法不处理任何异常，所有异常全部抛出
     */
    public byte[] hexStr2ByteArr(String strIn)
        throws Exception
    {
        byte[] arrB = strIn.getBytes();
        int iLen = arrB.length;

		//两个字符表示一个字节，所以字节数组长度是字符串长度除以2
        byte[] arrOut = new byte[iLen / 2];
        for (int i = 0; i < iLen; i = i + 2)
        {
            String strTmp = new String(arrB, i, 2);
            arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
        }
        return arrOut;
    }

    /**
     * 默认构造方法，使用默认密钥
     * @throws Exception
     */
    public SyncDES()
        throws Exception
    {
        this(strDefaultKey);
    }

    /**
     * 指定密钥构造方法
     * @param strKey 指定的密钥
     * @throws Exception
     */
    public SyncDES(String strKey)
        throws Exception
    {

    	Security.addProvider(new com.sun.crypto.provider.SunJCE());
        Key key = getKey(strKey.getBytes());

        encryptCipher = Cipher.getInstance("DES");
        encryptCipher.init(Cipher.ENCRYPT_MODE, key);

        decryptCipher = Cipher.getInstance("DES");
        decryptCipher.init(Cipher.DECRYPT_MODE, key);
    }

    /**
     * 加密字节数组
     * @param arrB 需加密的字节数组
     * @return 加密后的字节数组
     * @throws Exception
     */
    public byte[] encrypt(byte[] arrB)
        throws Exception
    {
        return encryptCipher.doFinal(arrB);
    }

    /**
     * 加密字符串
     * @param strIn 需加密的字符串
     * @return 加密后的字符串
     * @throws Exception
     */
    public String encrypt(String strIn) throws Exception {
        return byteArr2HexStr(encrypt(strIn.getBytes("utf-8")));
    }

    /**
     * 解密字节数组
     * @param arrB 需解密的字节数组
     * @return 解密后的字节数组
     * @throws Exception
     */
    public byte[] decrypt(byte[] arrB) throws Exception{
        return decryptCipher.doFinal(arrB);
    }

    /**
     * 解密字符串
     * @param strIn 需解密的字符串
     * @return 解密后的字符串
     * @throws Exception
     */
    public String decrypt(String strIn) throws Exception {
        return new String(decrypt(hexStr2ByteArr(strIn)),"utf-8");
    }

    /**
     * 从指定字符串生成密钥，密钥所需的字节数组长度为8位
     * 不足8位时后面补0，超出8位只取前8位
     * @param arrBTmp 构成该字符串的字节数组
     * @return 生成的密钥
     * @throws Exception
     */
    private Key getKey(byte[] arrBTmp) throws Exception {
        //创建一个空的8位字节数组（默认值为0）
        byte[] arrB = new byte[8];
        //将原始字节数组转换为8位
        for (int i = 0; i < arrBTmp.length && i < arrB.length; i++){
            arrB[i] = arrBTmp[i];
        }
        //生成密钥
        Key key = new javax.crypto.spec.SecretKeySpec(arrB, "DES");
        return key;
    }


    /**
	 * @param args
	 */
	public static void main(String[] args) {
		SyncDES d;
		try {
			d = new SyncDES();
			String pwd = d.encrypt("XinXi@BuQuan.com");
			System.out.println("####" + pwd + "%%%%");
			System.out.println(d.encrypt("18187864535"));
			System.out.println(d.encrypt("韦军"));
			System.out.println(d.encrypt("韦军1"));
			System.out.println(d.encrypt("13308843731"));
			String pwdTemp = d.decrypt("6ae80b0b20573e027af1d27207249c98a6a518d8b4098dbb");
			System.out.println("####" + pwdTemp + "%%%%");
			System.out.println(d.decrypt("430af54a3246e11ba48550ff80846fc7a9f678980cb8a82b"));
			System.out.println(d.decrypt("c78d57dce2fab8d3037c77b1bfa79252"));
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}
